diff options
Diffstat (limited to 'fs/nilfs2/direct.c')
-rw-r--r-- | fs/nilfs2/direct.c | 429 |
1 files changed, 429 insertions, 0 deletions
diff --git a/fs/nilfs2/direct.c b/fs/nilfs2/direct.c new file mode 100644 index 0000000..303d7f1 --- /dev/null +++ b/fs/nilfs2/direct.c @@ -0,0 +1,429 @@ +/* + * direct.c - NILFS direct block pointer. + * + * Copyright (C) 2006-2008 Nippon Telegraph and Telephone Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Written by Koji Sato <koji@osrg.net>. + */ + +#include <linux/errno.h> +#include "nilfs.h" +#include "page.h" +#include "direct.h" +#include "alloc.h" + +static inline __le64 *nilfs_direct_dptrs(const struct nilfs_direct *direct) +{ + return (__le64 *) + ((struct nilfs_direct_node *)direct->d_bmap.b_u.u_data + 1); +} + +static inline __u64 +nilfs_direct_get_ptr(const struct nilfs_direct *direct, __u64 key) +{ + return nilfs_bmap_dptr_to_ptr(*(nilfs_direct_dptrs(direct) + key)); +} + +static inline void nilfs_direct_set_ptr(struct nilfs_direct *direct, + __u64 key, __u64 ptr) +{ + *(nilfs_direct_dptrs(direct) + key) = nilfs_bmap_ptr_to_dptr(ptr); +} + +static int nilfs_direct_lookup(const struct nilfs_bmap *bmap, + __u64 key, int level, __u64 *ptrp) +{ + struct nilfs_direct *direct; + __u64 ptr; + + direct = (struct nilfs_direct *)bmap; + if ((key > NILFS_DIRECT_KEY_MAX) || + (level != 1) || /* XXX: use macro for level 1 */ + ((ptr = nilfs_direct_get_ptr(direct, key)) == + NILFS_BMAP_INVALID_PTR)) + return -ENOENT; + + if (ptrp != NULL) + *ptrp = ptr; + return 0; +} + +static __u64 +nilfs_direct_find_target_v(const struct nilfs_direct *direct, __u64 key) +{ + __u64 ptr; + + ptr = nilfs_bmap_find_target_seq(&direct->d_bmap, key); + if (ptr != NILFS_BMAP_INVALID_PTR) + /* sequential access */ + return ptr; + else + /* block group */ + return nilfs_bmap_find_target_in_group(&direct->d_bmap); +} + +static void nilfs_direct_set_target_v(struct nilfs_direct *direct, + __u64 key, __u64 ptr) +{ + direct->d_bmap.b_last_allocated_key = key; + direct->d_bmap.b_last_allocated_ptr = ptr; +} + +static int nilfs_direct_prepare_insert(struct nilfs_direct *direct, + __u64 key, + union nilfs_bmap_ptr_req *req, + struct nilfs_bmap_stats *stats) +{ + int ret; + + if (direct->d_ops->dop_find_target != NULL) + req->bpr_ptr = (*direct->d_ops->dop_find_target)(direct, key); + ret = (*direct->d_bmap.b_pops->bpop_prepare_alloc_ptr)(&direct->d_bmap, + req); + if (ret < 0) + return ret; + + stats->bs_nblocks = 1; + return 0; +} + +static void nilfs_direct_commit_insert(struct nilfs_direct *direct, + union nilfs_bmap_ptr_req *req, + __u64 key, __u64 ptr) +{ + struct buffer_head *bh; + + /* ptr must be a pointer to a buffer head. */ + bh = (struct buffer_head *)((unsigned long)ptr); + set_buffer_nilfs_volatile(bh); + + if (direct->d_bmap.b_pops->bpop_commit_alloc_ptr != NULL) + (*direct->d_bmap.b_pops->bpop_commit_alloc_ptr)( + &direct->d_bmap, req); + nilfs_direct_set_ptr(direct, key, req->bpr_ptr); + + if (!nilfs_bmap_dirty(&direct->d_bmap)) + nilfs_bmap_set_dirty(&direct->d_bmap); + + if (direct->d_ops->dop_set_target != NULL) + (*direct->d_ops->dop_set_target)(direct, key, req->bpr_ptr); +} + +static int nilfs_direct_insert(struct nilfs_bmap *bmap, __u64 key, __u64 ptr) +{ + struct nilfs_direct *direct; + union nilfs_bmap_ptr_req req; + struct nilfs_bmap_stats stats; + int ret; + + direct = (struct nilfs_direct *)bmap; + if (key > NILFS_DIRECT_KEY_MAX) + return -ENOENT; + if (nilfs_direct_get_ptr(direct, key) != NILFS_BMAP_INVALID_PTR) + return -EEXIST; + + ret = nilfs_direct_prepare_insert(direct, key, &req, &stats); + if (ret < 0) + return ret; + nilfs_direct_commit_insert(direct, &req, key, ptr); + nilfs_bmap_add_blocks(bmap, stats.bs_nblocks); + + return 0; +} + +static int nilfs_direct_prepare_delete(struct nilfs_direct *direct, + union nilfs_bmap_ptr_req *req, + __u64 key, + struct nilfs_bmap_stats *stats) +{ + int ret; + + if (direct->d_bmap.b_pops->bpop_prepare_end_ptr != NULL) { + req->bpr_ptr = nilfs_direct_get_ptr(direct, key); + ret = (*direct->d_bmap.b_pops->bpop_prepare_end_ptr)( + &direct->d_bmap, req); + if (ret < 0) + return ret; + } + + stats->bs_nblocks = 1; + return 0; +} + +static void nilfs_direct_commit_delete(struct nilfs_direct *direct, + union nilfs_bmap_ptr_req *req, + __u64 key) +{ + if (direct->d_bmap.b_pops->bpop_commit_end_ptr != NULL) + (*direct->d_bmap.b_pops->bpop_commit_end_ptr)( + &direct->d_bmap, req); + nilfs_direct_set_ptr(direct, key, NILFS_BMAP_INVALID_PTR); +} + +static int nilfs_direct_delete(struct nilfs_bmap *bmap, __u64 key) +{ + struct nilfs_direct *direct; + union nilfs_bmap_ptr_req req; + struct nilfs_bmap_stats stats; + int ret; + + direct = (struct nilfs_direct *)bmap; + if ((key > NILFS_DIRECT_KEY_MAX) || + nilfs_direct_get_ptr(direct, key) == NILFS_BMAP_INVALID_PTR) + return -ENOENT; + + ret = nilfs_direct_prepare_delete(direct, &req, key, &stats); + if (ret < 0) + return ret; + nilfs_direct_commit_delete(direct, &req, key); + nilfs_bmap_sub_blocks(bmap, stats.bs_nblocks); + + return 0; +} + +static int nilfs_direct_last_key(const struct nilfs_bmap *bmap, __u64 *keyp) +{ + struct nilfs_direct *direct; + __u64 key, lastkey; + + direct = (struct nilfs_direct *)bmap; + lastkey = NILFS_DIRECT_KEY_MAX + 1; + for (key = NILFS_DIRECT_KEY_MIN; key <= NILFS_DIRECT_KEY_MAX; key++) + if (nilfs_direct_get_ptr(direct, key) != + NILFS_BMAP_INVALID_PTR) + lastkey = key; + + if (lastkey == NILFS_DIRECT_KEY_MAX + 1) + return -ENOENT; + + BUG_ON(keyp == NULL); + *keyp = lastkey; + + return 0; +} + +static int nilfs_direct_check_insert(const struct nilfs_bmap *bmap, __u64 key) +{ + return key > NILFS_DIRECT_KEY_MAX; +} + +static int nilfs_direct_gather_data(struct nilfs_bmap *bmap, + __u64 *keys, __u64 *ptrs, int nitems) +{ + struct nilfs_direct *direct; + __u64 key; + __u64 ptr; + int n; + + direct = (struct nilfs_direct *)bmap; + if (nitems > NILFS_DIRECT_NBLOCKS) + nitems = NILFS_DIRECT_NBLOCKS; + n = 0; + for (key = 0; key < nitems; key++) { + ptr = nilfs_direct_get_ptr(direct, key); + if (ptr != NILFS_BMAP_INVALID_PTR) { + keys[n] = key; + ptrs[n] = ptr; + n++; + } + } + return n; +} + +int nilfs_direct_delete_and_convert(struct nilfs_bmap *bmap, + __u64 key, __u64 *keys, __u64 *ptrs, + int n, __u64 low, __u64 high) +{ + struct nilfs_direct *direct; + __le64 *dptrs; + int ret, i, j; + + /* no need to allocate any resource for conversion */ + + /* delete */ + ret = (*bmap->b_ops->bop_delete)(bmap, key); + if (ret < 0) + return ret; + + /* free resources */ + if (bmap->b_ops->bop_clear != NULL) + (*bmap->b_ops->bop_clear)(bmap); + + /* convert */ + direct = (struct nilfs_direct *)bmap; + dptrs = nilfs_direct_dptrs(direct); + for (i = 0, j = 0; i < NILFS_DIRECT_NBLOCKS; i++) { + if ((j < n) && (i == keys[j])) { + dptrs[i] = (i != key) ? + nilfs_bmap_ptr_to_dptr(ptrs[j]) : + NILFS_BMAP_INVALID_PTR; + j++; + } else + dptrs[i] = NILFS_BMAP_INVALID_PTR; + } + + nilfs_direct_init(bmap, low, high); + + return 0; +} + +static int nilfs_direct_propagate_v(struct nilfs_direct *direct, + struct buffer_head *bh) +{ + union nilfs_bmap_ptr_req oldreq, newreq; + __u64 key; + __u64 ptr; + int ret; + + key = nilfs_bmap_data_get_key(&direct->d_bmap, bh); + ptr = nilfs_direct_get_ptr(direct, key); + if (!buffer_nilfs_volatile(bh)) { + oldreq.bpr_ptr = ptr; + newreq.bpr_ptr = ptr; + ret = nilfs_bmap_prepare_update(&direct->d_bmap, &oldreq, + &newreq); + if (ret < 0) + return ret; + nilfs_bmap_commit_update(&direct->d_bmap, &oldreq, &newreq); + set_buffer_nilfs_volatile(bh); + nilfs_direct_set_ptr(direct, key, newreq.bpr_ptr); + } else + ret = nilfs_bmap_mark_dirty(&direct->d_bmap, ptr); + + return ret; +} + +static int nilfs_direct_propagate(const struct nilfs_bmap *bmap, + struct buffer_head *bh) +{ + struct nilfs_direct *direct; + + direct = (struct nilfs_direct *)bmap; + return (direct->d_ops->dop_propagate != NULL) ? + (*direct->d_ops->dop_propagate)(direct, bh) : + 0; +} + +static int nilfs_direct_assign_v(struct nilfs_direct *direct, + __u64 key, __u64 ptr, + struct buffer_head **bh, + sector_t blocknr, + union nilfs_binfo *binfo) +{ + union nilfs_bmap_ptr_req req; + int ret; + + req.bpr_ptr = ptr; + ret = (*direct->d_bmap.b_pops->bpop_prepare_start_ptr)( + &direct->d_bmap, &req); + if (ret < 0) + return ret; + (*direct->d_bmap.b_pops->bpop_commit_start_ptr)(&direct->d_bmap, + &req, blocknr); + + binfo->bi_v.bi_vblocknr = nilfs_bmap_ptr_to_dptr(ptr); + binfo->bi_v.bi_blkoff = nilfs_bmap_key_to_dkey(key); + + return 0; +} + +static int nilfs_direct_assign_p(struct nilfs_direct *direct, + __u64 key, __u64 ptr, + struct buffer_head **bh, + sector_t blocknr, + union nilfs_binfo *binfo) +{ + nilfs_direct_set_ptr(direct, key, blocknr); + + binfo->bi_dat.bi_blkoff = nilfs_bmap_key_to_dkey(key); + binfo->bi_dat.bi_level = 0; + + return 0; +} + +static int nilfs_direct_assign(struct nilfs_bmap *bmap, + struct buffer_head **bh, + sector_t blocknr, + union nilfs_binfo *binfo) +{ + struct nilfs_direct *direct; + __u64 key; + __u64 ptr; + + direct = (struct nilfs_direct *)bmap; + key = nilfs_bmap_data_get_key(bmap, *bh); + BUG_ON(key > NILFS_DIRECT_KEY_MAX); + ptr = nilfs_direct_get_ptr(direct, key); + BUG_ON(ptr == NILFS_BMAP_INVALID_PTR); + + return (*direct->d_ops->dop_assign)(direct, key, ptr, bh, + blocknr, binfo); +} + +static const struct nilfs_bmap_operations nilfs_direct_ops = { + .bop_lookup = nilfs_direct_lookup, + .bop_insert = nilfs_direct_insert, + .bop_delete = nilfs_direct_delete, + .bop_clear = NULL, + + .bop_propagate = nilfs_direct_propagate, + + .bop_lookup_dirty_buffers = NULL, + + .bop_assign = nilfs_direct_assign, + .bop_mark = NULL, + + .bop_last_key = nilfs_direct_last_key, + .bop_check_insert = nilfs_direct_check_insert, + .bop_check_delete = NULL, + .bop_gather_data = nilfs_direct_gather_data, +}; + + +static const struct nilfs_direct_operations nilfs_direct_ops_v = { + .dop_find_target = nilfs_direct_find_target_v, + .dop_set_target = nilfs_direct_set_target_v, + .dop_propagate = nilfs_direct_propagate_v, + .dop_assign = nilfs_direct_assign_v, +}; + +static const struct nilfs_direct_operations nilfs_direct_ops_p = { + .dop_find_target = NULL, + .dop_set_target = NULL, + .dop_propagate = NULL, + .dop_assign = nilfs_direct_assign_p, +}; + +int nilfs_direct_init(struct nilfs_bmap *bmap, __u64 low, __u64 high) +{ + struct nilfs_direct *direct; + + direct = (struct nilfs_direct *)bmap; + bmap->b_ops = &nilfs_direct_ops; + bmap->b_low = low; + bmap->b_high = high; + switch (bmap->b_inode->i_ino) { + case NILFS_DAT_INO: + direct->d_ops = &nilfs_direct_ops_p; + break; + default: + direct->d_ops = &nilfs_direct_ops_v; + break; + } + + return 0; +} |